PENERAPAN PELEPASAN BEBAN LEBIH (OLS) PADA TRANSFORMATOR DAYA 30 MVA 70/20 kV DI GARDU INDUK BOOM BARU PT. PLN (PERSERO)

Loading on the power transformer in the substation continues to increase exponentially with time, the future possibility of the transformer has a full load or beyond its capacity. Full load on the power transformer make shorten the life of the transformer and the transformer performance decreases. To anticipate this one takes the transformer overload protection relays that Over Load Shedding (OLS). Over Load Relay Shedding (OLS) works when the transformer load has reached its settings by disconnecting the load per feeder as early prevention before the power transformer trip due to the total load exceeds capacity . Because OLS relays including the OCR incoming 20 kV and the workings of the OLS tripping feeder 20 kV. Then all three relays must be coordinated. Keywords: short circuit, overcurrent relays, Overload Shedding, setting relays, transformers